Alvaro Herrera <alvherre@commandprompt.com> writes:
> So that's how Oracle supports ordered aggregates? Interesting -- we
> just got that capability but using a different syntax. Hmm, the
> SQL:200x draft also has <within group specification> which seems the
> standard way to do the ORDER BY stuff for aggregates ... Should we
> change the syntax?
No. The syntax we are using is also standard. As best I can tell,
WITHIN GROUP means something different --- the spec only defines it
for rank functions (RANK | DENSE_RANK | PERCENT_RANK | CUME_DIST)
and it's basically a shorthand form of a window function call.
I find it doubtful that it's actually necessary in Oracle's version
of listagg ...
regards, tom lane
